Wall street is bracing for the worse this morning. How will the markets react? It could be an ugly day for your 401(k). Rebecca jarvis is live on the floor of the stock exchange. Good morning, rebecrebecca. Reporter: Good morning. This morning, the international monetary fund is warning of an international global catastroe. Kons yeconsequences for all if the u.S. Were to default on the debt. They are the three levels of economic threat if a debt limit deal is not reached by thursday. First retirement savings and loans. A rapidly spreading dom know effect starting with the dow plunging. Loans get more expensive and more difficult to get. Everything from buying a home to a car costs more. Second, our confidence. Already shaken by the shutdown, consumer sentiment at a nine-month low. The more unsettled consumers feel, the less we spend. A not so happy holiday for retailers and could cost jobs. Last, our benefits. After thursday, the government can pay just two-thirds of its bills. That's $106 billion short. That could put timely payments to social security, medicare and veterans at risk. I'm taking a look at where the market will open here today. Looks like as many as 100 points lower as traders brace themselves for the volatility ahead. Many are watching. Even though it's a holiday, markets are open. Now to the huge party boat

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